TY  - RPRT
TI  - Use of stable isotopes of carbon, nitrogen, and sulfur to identify sources of nitrogen in surface waters in the lower Susquehanna River basin, Pennsylvania
AU  - Charles A. Cravotta
PY  - 2002
DO  - 10.3133/wsp2497
UR  - https://pubs.usgs.gov/publication/wsp2497
ID  - wsp2497
ER  -